soundproof room
A room designed to block external noise or prevent sound from escaping, used in recording studios, practice rooms, and industrial settings.
He built a soundproof room at home and practices piano until late at night.
The soundproof room in this studio completely blocks outside noise.
無響室 is an anechoic chamber designed to absorb all sound reflections, used for acoustic testing, whereas 防音室 focuses on blocking sound transmission.
Compound of 防音 (ぼうおん, 'soundproofing') and 室 (しつ, 'room').